Water-repellent coatings or articles are mentioned or disclosed in, for example, U.S. Pat. No. 6,800,354, which discloses self cleaning surfaces formed by applying a coating having particles having an average particle size of less than 100 nanometers on the surface of a substrate. The U.S. Pat. No. 6,800,354 patent also discloses forming a nanoscale structure over a microscale structure where the nanoscale particles and microscale particles are distributed in the same coating or a first coating having microscale particles is applied to a substrate and a second coating with nanoscale particles is applied to the substrate. The coating may be made hydrophobic by treatment with a hydrophobizing substance such as an organosilane.
Self-cleaning hydrophobic structures are disclosed in U.S. Patent Publication No. US 2003/0013795. This application discloses a self-cleaning hydrophobic surface formed from particles secured with a carrier that includes a binder and particles. The surface is said to be self-regenerating by exposing new structure forming particles, which are released by way of UV light and the effects of wind and weather.